David Lowe
Modified phase table in stepper.cpp to enable stepping a bipolar motor using a twin H-bridge driver.
Fork of
stepper
by 
Kenji Arai
Corrected single-stepping, now walking up or down just one phase table. Compile-time options for driving bipolar motor in any of single-phase, two-phase, or half-stepping. Coils remain engaged at end of specifed movement command - de-energize coils by issuing a motor.move(0) while already stopped.
Diff: stepper.cpp
- Revision:
- 0:7b0c724fa658
- Child:
- 2:fd11d89b8ce0
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/stepper.cpp Sat Aug 23 06:34:07 2014 +0000
@@ -0,0 +1,236 @@
+/*
+ * mbed library program
+ * Stepping Motor
+ *
+ * Copyright (c) 2014 Kenji Arai / JH1PJL
+ * http://www.page.sannet.ne.jp/kenjia/index.html
+ * http://mbed.org/users/kenjiArai/
+ * Created: August 20th, 2014
+ * Revised: August 23rd, 2014
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
+ * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
+ * AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include "mbed.h"
+#include "stepper.h"
+
+const uint8_t pase_cw[4][4] = {{1, 1, 0, 0}, {0, 1, 1, 0}, {0, 0, 1, 1}, {1, 0, 0, 1}};
+const uint8_t pase_ccw[4][4] = {{1, 1, 0, 0}, {1, 0, 0, 1}, {0, 0, 1, 1}, {0, 1, 1, 0}};
+extern uint8_t pls_width[];
+
+STEPPER::STEPPER (PinName xp, PinName xn, PinName yp, PinName yn):
+ _xp(xp), _xn(xn), _yp(yp), _yn(yn) {
+ init();
+}
+
+void STEPPER::move (int32_t steps){
+ if (steps < 0){
+ inf.direction = D_CCW;
+ steps = -steps;
+ } else {
+ inf.direction = D_CW;
+ }
+ inf.total_step = steps;
+ setup_mtr_drv_dt(&inf, &cntl);
+}
+
+void STEPPER::set_max_speed (uint32_t time_base_us){
+ if (time_base_us < (MT_PLS_WIDTH_MIN * 1000)){
+ time_base_us = (MT_PLS_WIDTH_MIN * 1000);
+ }
+ _smdrv.attach_us(this, &STEPPER::millisec_inteval, time_base_us);
+}
+
+uint8_t STEPPER::status (void){
+ return cntl.state;
+}
+
+void STEPPER::init(void){
+ busy_sm_drv = 0;
+ _xp = 0;
+ _xn = 0;
+ _yp = 0;
+ _yn = 0;
+}
+
+void STEPPER::set4ports (uint32_t step, int8_t dir){
+uint8_t i;
+
+ i = (uint8_t)(step % 4);
+ if (dir == D_CW) {
+ _xp = pase_cw[i][0];
+ _xn = pase_cw[i][1];
+ _yp = pase_cw[i][2];
+ _yn = pase_cw[i][3];
+ } else {
+ _xp = pase_ccw[i][0];
+ _xn = pase_ccw[i][1];
+ _yp = pase_ccw[i][2];
+ _yn = pase_ccw[i][3];
+ }
+}
+
+void STEPPER::setup_mtr_drv_dt(Motor_Inf *mi, Motor_Control *mt){
+ busy_sm_drv = 1;
+ if (mi->total_step == 0){
+ if (mt->state != M_STOP){
+ mt->state = M_CHANGE;
+ mt->change_cnt = 5;
+ mt->pls_width = 0;
+ mt->ongoing = 0;
+ mt->up_cnt = 0;
+ mt->up_cnt_keep = 0;
+ mt->down_cnt = 0;
+ mt->continue_cnt = 0;
+ }
+ busy_sm_drv = 0;
+ return;
+ }
+ if ((mt->state == M_CONTINUE) && ( mt->direction == mi->direction)){
+ if (mi->total_step < MT_SLOP_STEP){
+ mt->up_cnt = 0;
+ mt->up_cnt_keep = 0;
+ mt->down_cnt = mi->total_step;
+ mt->continue_cnt = 0;
+ mt->state = M_DOWN;
+ mt->ongoing = 0;
+ } else {
+ mt->up_cnt = 0;
+ mt->up_cnt_keep = 0;
+ mt->down_cnt = MT_SLOP_STEP -1;
+ mt->continue_cnt = mi->total_step - (MT_SLOP_STEP - 1);
+ }
+ } else {
+ if ((mt->state == M_CONTINUE) && ( mt->direction != mi->direction)){
+ mt->state = M_CHANGE;
+ mt->change_cnt = 5;
+ } else {
+ mt->motor_step = 0;
+ mt->state = M_UP;
+ }
+ mt->pls_width = 0;
+ mt->ongoing = 0;
+ mt->direction = mi->direction;
+ if (mi->total_step < MT_MIN_STEP){
+ if (mi->total_step == MT_MIN_STEP - 1){
+ mt->up_cnt = MT_SLOP_STEP;
+ } else {
+ mt->up_cnt = mi->total_step / 2;
+ }
+ mt->up_cnt_keep = mt->up_cnt;
+ mt->down_cnt = mi->total_step - mt->up_cnt;
+ mt->continue_cnt = 0;
+ } else {
+ mt->up_cnt = MT_SLOP_STEP;
+ mt->up_cnt_keep = mt->up_cnt;
+ mt->down_cnt = MT_SLOP_STEP -1 ;
+ mt->continue_cnt = mi->total_step - MT_SLOP_STEP - (MT_SLOP_STEP - 1);
+ }
+ }
+ busy_sm_drv = 0;
+}
+
+void STEPPER::millisec_inteval() {
+ if (busy_sm_drv == 1){ return;}
+ switch (cntl.state){
+ case M_STOP:
+ _xp = 0;
+ _xn = 0;
+ _yp = 0;
+ _yn = 0;
+ break;
+ case M_UP:
+ if (cntl.ongoing){
+ if (--cntl.pls_width == 0){
+ if (--cntl.up_cnt == 0){
+ cntl.ongoing = 0;
+ if (cntl.continue_cnt == 0){
+ cntl.state = M_DOWN;
+ } else {
+ cntl.state = M_CONTINUE;
+ }
+ } else {
+ set4ports(cntl.motor_step, cntl.direction);
+ cntl.motor_step++;
+ cntl.pls_width = pls_width[cntl.up_cnt_keep - cntl.up_cnt];
+ }
+ } else {
+ break;
+ }
+ } else { // 1st entry from M_STOP
+ set4ports(cntl.motor_step, cntl.direction);
+ cntl.motor_step++;
+ cntl.pls_width = pls_width[cntl.up_cnt_keep - cntl.up_cnt];
+ cntl.ongoing = 1;
+ }
+ break;
+ case M_CONTINUE:
+ set4ports(cntl.motor_step, cntl.direction);
+ cntl.motor_step++;
+ if (--cntl.continue_cnt == 0){
+ cntl.ongoing = 0;
+ cntl.state = M_DOWN;
+ }
+ break;
+ case M_DOWN:
+ if (cntl.ongoing){
+ if (--cntl.pls_width == 0){
+ if (--cntl.down_cnt == 0){
+ cntl.ongoing = 0;
+ cntl.state = M_STOP;
+ }else {
+ set4ports(cntl.motor_step, cntl.direction);
+ cntl.motor_step++;
+ cntl.pls_width = pls_width[cntl.down_cnt];
+ }
+ } else {
+ break;
+ }
+ } else { // 1st entry from M_UP or M_CONTINUE
+ set4ports(cntl.motor_step, cntl.direction);
+ cntl.motor_step++;
+ cntl.pls_width = pls_width[cntl.down_cnt];
+ cntl.ongoing = 1;
+ }
+ break;
+ case M_CHANGE:
+ if (cntl.ongoing){
+ if (--cntl.pls_width == 0){
+ if (--cntl.change_cnt == 0){
+ cntl.ongoing = 0;
+ if (cntl.up_cnt == 0){
+ cntl.state = M_STOP;
+ } else {
+ cntl.state = M_UP;
+ }
+ }else {
+ if (cntl.direction == D_CW){
+ set4ports(cntl.motor_step, D_CCW);
+ } else {
+ set4ports(cntl.motor_step, D_CW);
+ }
+ cntl.motor_step++;
+ cntl.pls_width = pls_width[cntl.change_cnt];
+ }
+ } else {
+ break;
+ }
+ } else { // 1st entry
+ if (cntl.direction == D_CW){
+ set4ports(cntl.motor_step, D_CCW);
+ } else {
+ set4ports(cntl.motor_step, D_CW);
+ }
+ cntl.motor_step++;
+ cntl.pls_width = pls_width[cntl.change_cnt];
+ cntl.ongoing = 1;
+ }
+ break;
+ default :
+ cntl.state = M_STOP;
+ }
+}